Sequential thermally responsive switch mechanism



y 1966 J. w. HUFFMAN ETAL 3, 4,184

SEQUENTIAL THERMALLY RESPONSIVE SWITCH MECHANISM Filed July 9, 1964 INVENTORS Jaw M Harm/w & BY F/PAAM I fl/ncfl/r United States Patent 0 3,254,184 SEQUENTIAL THERMALLY RESPONSIVE SWITCH MECHANISM John W. Huffman and Frank T. Piacent, Mansfield, Ohio,

assignors to Pace, Inc., Mansfield, Ohio, a corporation of Ohio Filed July 9, 1964, Ser. No. 381,352 11 Claims. (Cl. 200138) This invention relates to switch mechanism and more especially to a dual switch mechanism in which a single manually adjustable means is arranged to establish dual circuits in association with thermoresponsive means for automatically controlling one of the circuits after its initial establishment by the manual means.

In certain instrumentalities or appliances it is imperative to effect the energization of one current consuming instrumentality or component prior to the energization of a second current consuming instrumentality, especially where the latter instrumentality may'be dependent for its efiective use upon the prior energization of the first instrumentality. One example of the utility of a dual switch means of this character is in association with a conventional hair dryer unit embodying a motor driven air blower or fan which is brought into operation prior to the energization "of the heating element of the hair dryer unit and wherein the heating element is de-energized prior to the de-energization of the motor driving the blower or fan.

In most conventional hair dryers in use at the present time, a blower motor circuit is energized and thereafter resistance heaters are successively brought into operation by step switch means, different degrees of temperature being provided by manual adjustment of the step switch to successively intercalate resistance heaters in an energizing circuit through successive manual adjustments. In such hair dryer constructions, the heat is increased or decreased in stepped increments as the individual resistance heaters of fixed values are successively energized or de-energized to provide different temperatures without gradation from one temperature to another.

The present invention pertains to a switch mechanism providing a dual circuit control means for two ehergizable circuits wherein manipulation or adjustment of one switch member initiates energization or de-energization of dual current consuming instrumentalities.

An object of the invention is the provision of a switch mechanism wherein one switch means through manual manipulation effects sequential control of two circuits and, when the means is adjusted for a particular temperature for an electrically energizable heater, that such temperature is automatically maintained by a thermoresponsive medium operative upon a portion of the switch means without affecting one of the circuits.

An object of the invention embraces the provision of a dual switch mechanism in which dual circuit establishing switch means is manually adjustable in association with a thermoresponsive medium or component arranged to maintain control of one of the circuits after its initial establishment by the manually adjustable means.

Another object of the invention is the provision of a dual switch mechanism having particular utility in controlling dual current consuming instrumentalities through manual adjustment of a single member which is distortable to sequentially energize or de-energize two circuits wherein the member may be adjusted to a particular setting for obtaining a desired temperature for an instrumentality in one of the circuits and the desired temperature maintained automatically by thermoresponsive means.

Another object of the invention is the provision of a switch mechanismembodying a compound switch mem- 3,254,184 Patented May 31, 1966 "ice her for sequentially controlling two circuits, the switch .member being fashioned with two flexible or distortable portions functioning as dual controls for two circuits whereby one portion is effective to control one circuit and another portion rendered effective to control the other .circuit in conjunction with a thermoresponsive medium efiective to control one circuit but having no effect upon the other circuit.

Another object of the invention is the provision of a dual switch mechanism embodying manual control for a distortable switch component for establishing or interrupting both circuits in conjunction with a thermoresponsive control for one circuit wherein the mechanism embodies a minimum number of components and is of compact character occupying a comparatively small space and which is inexpensive to manufactureand is reliable in operation.

Further objects and advantages are within the scope of this invention such as relate to the arrangement, operation and function of the related elements of the structure, to various details of construction and to combinations of parts, elements per se, and to economics of manufacture and numerous other features as will be apparent from a consideration of the specification and drawing of a form of the invention, which may be preferred, in which:

FIGURE 1 is a longitudinal sectional view through the switch mechanism of the invention, the view being on an enlarged scale;

FIGURE 2 is an isometric expanded view of the several components of the switch mechanism;

FIGURE 3 is an end view of the construction shown in FIGURE 1;

and including a schematic circuit diagram for two current consuming instrumentalities controlled by the switch mechanism;

FIGURE 5 is an isometric view showing a modified form for one of the components of the switch mechanism, and

FIGURE 6 illustrates a modified form of the switch construction.

While the switch mechanism of the invention is particularly adapted for controlling an air blower and electrically energizable heating means of a hair drying apparatus, it is to be understood that the switch mechanism may be employed for other purposes for controlling other instrumentalities wherever it may be found to have utility.

Referring to the drawings in detail and initially to the form of'the invention shown in FIGURES 1 through 4, the switch mechanism is inclusive of a support means 10 which, in the embodiment illustrated comprises a planar member or plate 12 and a hollow cylindrical metal member 14, the latter being interiorly threaded as at 16 to accommodate a mounting member or screw 18. A portion of a housing 20 illustrated in FIGURE 1, which may be the housing construction of a hair dryer, the screw 18 serving to secure the switch mechanism to the housing 20.

The switch mechanism of the invention is inclusive of a manually operable means for adjusting the relative position of a single switch member configurated or fashioned to energize and de-energize dual circuits as hereinafter described. The support plate or component 12 is provided with an opening to receive a tenon portion of a bushing 22, the lower end of the bushing being swaged in assembly as at 24 into securing relation with the plate 12, as particularly shown in FIGURE 1.

The bushing 20 is interiorly threaded to receive a threaded shaft or stem 26, the upper end of the shaft 26 supporting a manipulating knob 28 of suitable insulating material, the knob being provided with a transverse 3 threaded opening accommodating a securing screw 30 adapted to be drawn into engagement with the shaft 26 to secure the knob on the shaft. The lower end of the shaft 26 is provided with a bore 32 in which is disposed a rigid member or strut 34 of lava or other suitable high temperature resistant insulating material.

The rotational movement of the shaft or stem 26, through its threaded engagement with the bushing 22, adjusts the position of a switch memberhereinafter described. The bushing 22 is provided with an upwardly extending projection or abutment 36, and the shaft 26 is equipped with a transversely extending pin 38, the pin 38 cooperating with the projection or abutment 36 for limiting the rotational movement of the shaft 26.

v The switch mechanism is inclusive of a first switch member 40, herein referred to as a compound switch member in that it is of flexible metal fashioned with a first switch arm or section 42 and a second switch arm or section 42 and a second switch arm or section 44. The shape of the switch member 40 is particularly shown in FIGURE 2 where it will be seen that a slot 46 is formed lengthwise of the switch member 40, the slot terminating at its forward end at a lateral edge 48. The forward end v region of the switch arm or section. 42 is provided with a contact 50.

The switch arm or section 44 of the compound switch member 40 is formed by slitting the material to form the lateral edge 48 and forming or bending the terminal region of the portion 44 to a V-shaped configuration, as shown in FIGURES 1 and 2, the apex 54 of the V-shaped configuration being a contact or a contact portion for the switch arm or section 44. The several components of the switch mechanism are arranged or mounted in stacked relation on an insulating means such as a sleeve or bushing 58 which is telescoped onto the cylindrically shaped member 14, the insulating means 58 having at its upper end an outwardly extending flange 60.

The compound switch member is fashioned with an opening 62 whereby the switch member is snugly received on the insulating bushing 58. A first terminal member 64 is fashioned with an opening 65 to be received on the insulating bushing 58 and engages or abuts the flange 60. The compound switch member 40 is assembled on the sleeve in metallic engagement or contact with the first terminal member 64, as particularly shown in FIGURE 1. A third switch member 68 is fashioned with an opening 69 of a dimension to be received on the insulating bushing 58, the switch member 68 being fashioned with a terminal portion 70, hereinsreferred to as a second tenminal means.

The switch member 68 is assembled on the insulating bushing 58 with an insulating member or washer 72 disposed between the compound switch member 40 and the switch member 68. The arrangement embodies a thermoresponsive medium or bimetal element 76 which, in the embodiment illustrated, serves or functions as a fourth switch arm. The bimetal element or fourth switch arm is provided with a contact 78 arranged for cooperation with the contact 50 carried by the first switch arm or section 42 of the compound switch member 40.

The bimetal element 76 is fashioned with an opening 79 of a dimension whereby the bimetal element is received on the insulating means or bushing 58 in the manner illustrated in FIGURE 1. An insulating member or washer 80 is assembled on the bushing 58 disposed between the third switch member 68 and the bimetal element or fourth switch member 76. In assembly, a washer or spacer 82 of insulating material is disposed between a flange 15 formed on the lower end of the support member 14 and the bimetal element 76 to insulate the bimetal element from the metal support. The bimetal element 76 is formed with a terminal portion 84 herein referred to as the third terminal portion.

After the several components of the switch mechanism hereinbefore described are assembled on the insulating 4 sleeve or bushing 58, an end region of the tubular portion 14 of the support means projects through the bushing 58.

The upper end thereof, extending above the support plate 12, is swaged as shown at 86 into snug engagement with the upper surface of the support member or plate 12 as shown in FIGURE 1 to retain the several switch components in assembled relation.

The compound switch member 40 is preferably fashioned of beryllium copper, an. alloy of beryllium and copper having high strength properties and good current conducting characteristics and which is not subject to appreciable oxidation where it is used as a contact making and breaking means in an electric circuit of low amperage. As shown in FIGURE 1 a compound switch member 40 which includes both the first switch arm portion 42 and the second arm portion 44 is prestressed or inherently tensioned so as to be normally biased upwardly into contact with the end of the strut member or insulating means 34 disposed in the recess of the shaft 26.

In an off position of the manually rotatable shaft 26 with the pin 38 in engagement with the abutment 36, the contacts 50 and 78 are out of engagement and the contact portion 54 of the switch arm 44 is out of contact with the switch member 68.

FIGURE 4 illustrates schematically the circuit connections for the switch mechanism in installations where the switch mechanism is arranged to control a blower drive motor and a heater construction of a hair dryer appliance.

As shown in FIGURE 4, the current conductors or lines L1 and L2 are conected with a conventional current supply. The power supply line L1 is connected to the first terminal portion 64 which is in metallic contact with the compound switch member 40.

The motor 90, adapted to drive or rotate a fan or air blower of the hair dryer appliance, is connected by a lead 91 with the current supply line L2 and with a second lead 92 with the second terminal portion 70 formed as an integral part of the switch member 68. The heater element 94 of the hair dryer appliance is connected by a lead or conductor 95 with the line L2 and by a conductor 96 with the third terminal portion 84 which is an integral component of the bimetal element 76 providing the fourth switch member of the switch mechanism.

The bimetal element 76 is fashioned of metals having different coefficients of expansion whereby an increase in ambient temperature causes the bimetal element to flex downwardly, as viewed in FIGURE 1, in a direction to separate the contacts 50 and 78 and to flex upwardly upon a decrease in the ambient temperature.

In the use of the switch arrangement in a hair dryer appliance it is essential that the air blower, driven by the motor .90, be in operation at all times during energization of the hair dryer heating element 94, and it is therefore important that the blower motor be energized prior to energization of the heater element 94, and that the de-energization of the motor 90 take place after the heating element 94 has been de-energized.

The operation of the switch mechanism of the invention is as follows: The components of the switch mechanism, as illustrated in FIGURE 1, are in circuit deenergizing positions. In this off position, the pin 38 shown in FIGURE 2 is in engagement with the abutment 36. As the shaft 26 is rotated by the knob 28 in a clockwise direction, as viewed in FIGURE 2, the strut 34 in engagement with the upper surface of the compound switch member 40 flexes the switch member downwardly including both flexible switch arms 42 and 44.

This initial partial rotation of the knob 28 and shaft 26 engages the apexor raised contact portion 54 of the second switch arm or switch section 44 with the third switch arm 68, thus completing the circuit through the motor 90- thereby initiating operation of the air blower. Rotation of the manipulating knob 28 is continued, depending upon the degree of heat to be maintained in the appliance. A dial (not shown) may be mounted on the housing 20 containing graduations indicating various degrees of heat and the knob provided with an index for cooperation with the graduations on the dial in a conventional manner.

This further rotation of the knob 28 then engages the contact 50 of the first switch arm 42 with the contact 78 on the bimetallic element or fourth switch arm 76, thereby completing the circuit to the heater 94 and energizing the heater.

-As the ambient temperature in the region of the bimetal element 76 is. increased under the influence of the heat generated by the electrically energizable heater 94, the bimetal element 76 flexes downwardly and interrupts the circuit through the heating element 94 by moving the contact 78 out of engagement with the contact 50.

This action of the thermoresponsive element or bimetal element 76 occurs independently of the position of the contact member 54 which remains in engagement with the switch member 68 by the strut 34 to maintain the air blower driven by motor 90 in operation. When the ambient temperature decreases by de-energization of the heater element 94, the bimetal element 76 flexes upwardly to again engage the contacts 50 and 78 and reenergize the heater 94. In this manner the temperature desired is maintained substantially constant through the repeated or cycling engagement and disengagement of the contacts 50 and 78 to control the heater circuit.

If an increased degree of heat is desired for the hair dryer appliance, the knob 28 is rotated further in a clockwise direction which moves the switch arm 42 and contact 50 further downwardly whereby a higher temperature is required in the region of the bimetal element to disengage the contacts 50 and 78. Thus, through manipulation of the knob 28 to a particular adjusted position, any desired degree of heating may be attained within the range of rotation of the shaft 26 and the temperature desired maintained substantially constant for the particular temperature setting.

The switch arm 68 is fashioned of metal of a thickness greater than that of the compound switch means 40 so as not to be distort'able under the pressure exerted by the switch arm or portion 44 of the switch member 40. The material of the switch member 68 is however of a thickness such that it may be bent a slight amount in order to calibrate its initial position with respect to the contact portion 54 of the switch arm 44 when the knob 28 and shaft 26 are in an off position whereby in such position the contact portion 54 is out of contact with the switch member 68.

In assembly, the switch member 68 may be slightly deformed or bent to attain this calibration. For such purpose the support plate 12 is fashioned with an opening 98 and the compound switch member 40 fashioned with an opening 99 which, in assembly, is aligned with the opening 98 to receive a suitable tool for calibrating or adjusting the initial position of the distal portion of the switch member 68.

FIGURE 5 illustrates a modified form of the third switch member or arm engaged. by the contact portion 54 of switch arm 44. In this form the switch member 68' has the switch arm portion formed into V-shaped configuration as indicated at 100 providing an apex line 102 which, when embodied in the switch assembly, is adapted to be engaged by the contact portion 54 of the switch arm 44 to complete the circuit through the air blower motor 90.

By fashioning the switch arm portion 100 of V-shaped configuration, the region of engagement of the apex 54 of the switch arm 44 with the apex line 102 of the switch member 68' provides substantially a point-to-point contact in circuit closing position.

FIGURE 6 illustrates the switch mechanism embodying a modification of the switch arm construction for controlling one of the circuits. The plate 12a and the member 14a provides support means for the switch components in the same manner as illustrated in FIGURE 1,

the components including a compound switch member 40, a third switch arm 68a, a bimetal element 76a forming the fourth switch arm, and terminal members or portions 64a, 70a and 84a assembled in the same manner as the corresponding components shown in FIGURE 1. In the form shown in FIGURE 6, the compound switch member 40a is fashioned with an L-shaped slot 106 which provides a flexible first switch arm 42a and a flat flexible second switch arm 44a, the arms 42a and 44a being fashioned as integral components of the compound switch member 40a. In this form of construction, the member 68a is preferably fashioned with an upwardly extending distal end portion 108 which is adapted to be engaged by the flexible switch arm or section 440 when the shaft 26a is initially rotated away from off position.

Thus, in this form, a line contact is made between the I upwardly extending portion 108 of the comparativelyrigid switch arm 68a and the flat flexible switch arm 44a for controlling the circuit of the motor driving an air blower or fan. The flexible switch arm 42a is provided with a contact 50a arranged for cooperation with the contact 7 8a mounted on the bimetal element 76a, these contacts cooperating to control the circuit through the heater 94 in the manner hereinbefore described in reference to the construction shown in FIGURES 1 through 4. 5

When the shaft 26a is rotated from a circuit-closing position to ofi position, the switch arm 44a and the contact portion 108 are out of engagement and the contacts 50a and 78a are out of engagement. Upon rotation of the shaft 26ain a circuit-closing direction, the circuit for the motor 90 is completed through engagement of the switch arm 44a with the contact portion 108 and, upon further rotation of the shaft 26a, the flexible switch arm 42a is flexed further downwardly to engage the contacts 94. Thereafter, the bimetal element or thermoresponsive medium 76a, under the influence of heat generated by the heater 94, automatically controls current flow through the heater 94 substantially at a temperautre for which the rotatable shaft 26a has been adjusted.

It is apparent that, within the scope of the invention, modifications and different arrangements may be made other than as herein disclosed, and the present disclosure 1s illustrative merely, the invention comprehending all variations thereof. 9

We claim:

1. Switch mechanism comprising, in combination, support means, a switch member mounted by the support means shaped to provide a first switch arm and a second switch arm, said first and second switch arms being flexlble, manually operable means mounted by the .support means engageable with the switch member for actuating the first and second switch arms, a substantially rigid third switch arm mounted by the support means arranged to be engaged by the second switch arm to control a first circult, a thermoresponsive element mounted by the support means, contacts carried by the first switch arm and said element arranged to be engaged and disengaged for controlling a second circuit, said first and second switch arms being movable by said manually operable means to positions whereby the first circuit is established during the periods that the second circuit is established through the first switch arm and the thermoresponsive element.

2. Switch mechanism comprising, in combination, support means, a switch member of beryllium copper alloy mounted by the support means shaped to provide a first switch arm and a second switch arm, said first and second switch arms being flexible, manually operable means mounted by the support means engageable with the switch member for actuating the first and second switch arms, a third switch arm mounted by the support means arranged to be engaged by the second switch arm to control a first circuit, a thermoresponsive element mounted by the support means, contacts carried by the first switch arm and said element arranged to be engaged and disengaged for controlling a second circuit, said first and second switch arms being actuated by said manually operable means to positions whereby the first circuit is established during the periods that the second circuit is established through the first swtich arm and the thermoresponsive element.

3. 7 Switch mechanism comprising, in combination, support means, a switch member mounted by the support means shaped to provide a first switch arm and a second switch arm, said first and second switch arms being flexible, said second switch arm having a raised contact portion, manually operable means mounted by the support means engageable with the switch member for flexing the first and second switch arms, a third switch arm mounted by the support means arranged to be engaged by the raised contact portion of the second switch arm to control a first circuit, a bimetal element mounted by the support means, contacts carried by the first switch arm and said element arranged to be engaged and disengaged for controlling a second circuit, said first and second switch arms being flexed by said manually operable means to positions whereby the first and second circuits are established in sequence.

4. Switch mechanism comprising, in combination, support means, a switch member of beryllium copper alloy mounted by the support means having an L-shaped slot providing a first switch arm and a second switch arm, said first and second switch arms being flexible, manually operable means mounted by the support means engageable with the switch member for flexing the first and second switch arms, a substantially rigid third switch arm mounted by the support means arranged to be engaged by the second switch arm to control a first circuit, a thermoresponsive element mounted by the support means, contacts carried by the first switch arm and said element arranged to be engaged and disengaged for controlling a second circuit, said first and second switch arms being arranged to be flexed by said manually operable means to positions whereby the first circuit is established during the periods that the second circuit is established through the first switch arm and the thermoresponsive element.

5. Switch mechanism comprising, in combination, support means including a plate member and a cylindrical member, said members being secured together, insulating means mounted on the cylindrical member, a flexible switch member mounted by the insulating means, a slot in said switch member providing a first switch arm and a second switch arm, a third switch arm mounted by the insulating means, said third switch arm being substantially rigid and arranged to be engaged by the second switch arm, a flexible bimetal element mounted by the insulating means, said first switch arm and bimetal element being provided with cooperating contacts, a threaded bushing mounted on the support plate, a rotatable shaft having a threaded portion cooperating with the threaded portion of the bushing, strut means of insulating material disposed between said rotatable shaft and the switch member, said shaft and strut being arranged whereby rotation of the shaft in one direction flexes said second switch arm into contact with the third switch arm and flexes the first switch arm to engage the contact on the first switch arm with the contact on the bimetal element.

6. Switch mechanism comprising, in combination, support means including a plate member and a cylindrical member, said members being secured together, insulating means mounted on the cylindrical member, a flexible switch member of beryllium copper alloy mounted by the insulating means, an L-shaped slot in the switch member providing a first switch arm and a second switch arm, a third switch arm mounted by the insulating means, said third switch arm being substantially rigid and arranged to be engaged by the second switch arm, a flexible bimetal element mounted by the insulating means, said first switch arm and bimetal element being provided with cooperating contacts, a threaded bushing mounted on the support plate, a rotatable shaft having a threaded portion cooperating with the threaded portion of the bushing, strut means of insulating material disposed between said rotatable shaft and the switch member, said shaft and strut being arranged whereby rotation of the shaft in one direction flexes said second switch arm into contact with the third arm and upon further rotation to engage the contact on the firts switch arm with the contact on the bimetal element to sequentially energize a first circuit through the second and third switch arms and a second circuit through the first switch arm and the bimetal element.

7. Switch mechanism comprising, in combination, support means including a plate member and a cylindrical member, said members being secured together, insulating means mounted on the cylindrical member, a flexible switch member mounted by the insulating means and having a slot therein providing a first switch arm and a second switch arm, a first terminal for said switch member, a third switch arm mounted by the insulating means and shaped to provide a second terminal, said third switch arm being substantially rigid and arranged to be engaged by the second switch arm, a flexible bimetal element and a third terminal associated therewith, said first switch arm and bimetal element being provided with cooperating contacts, a threaded bushing mounted on the support plate, a rotatable shaft having a threaded portion cooperating with the threaded portion of the bushing, strut means of insulating material disposed between said rotatable shaft and the switch member, said shaft and strut being arranged where-by rotation of the shaft in one direction flexes said second switch arm into contact with the third switch arm and upon further rotation to engage the contact on the first'switch arm with the contact on the bimetal element to energize a first circuit through the second and third switch arms and a second circuit through the first switch arm and the bimetal element, said first terminal being connected with one side of a power supply and the second and third terminals connected with correct consuming instrumentalities and the current consuming instrumentalities connected with the other side of the power supply.

8. Switch mechanism comprising, in combination, support means including a plate member and a cylindrical member, said members being secured together, insulating means mounted on the cylindrical member, a flexible switch member mounted by the insulating means having a slot therein providing a first switch arm and a second switch arm, said second switch arm having a raised portion, a third switch arm mounted by the insulating means, said third switch arm being substantially rigid and adapted to be engaged by the second switch arm, a flexible bimetal element mounted by the insulating means, said first switch arm and bimetal element being provided with cooperating contacts, individual terminal means associated with the switch member, the third switch arm and the Ibimetal element, a threaded bushing mounted on the support plate, a rotatable shaft having a threaded portion cooperating with the threaded portion of the bushing, a rigid strut of insulating material disposed between the rotatable shaft and the switch member, the terminal associated with the switch member being adapted to be connected with one side of a current supply, the terminals associated with the third switch arm and the bimetal element being adapted to be respectively connected with a motor and an electrically energizable heater, said switch arms being arranged whereby rotation of the shaft in one direction first engages thesecond and third switch arms to energize the circuit through the motor and further rotation of the shaft engaging the contacts on the first switch arm and bimetal element to energize the circuit through said heater.

9. Switch mechanism comprising, in combination, support means including aplate member and a cylindrical member, said members being secured together, insulating means mounted on the cylindrical member, a flexible switch member mounted by the insulating means having a slot therein providing afirst switch arm and a second switch arm, a third switch arm mounted 'by the insulating means, said third switch arm being substantially rigid and the distal portion thereof configurated with a V-shape providing an apex adapted to be engaged by the second switch arm, a flexible bimetal element mounted by the insulating means, said first switch arm and bimetal element being provided with cooperating contacts, a threaded bushing mounted on the support plate, a rotatable shaft having a threaded portion cooperating with the threaded portion of the bushing, a rigid strut of insulating material disposed between the rotatable shaft and the switch member, said switch arms being arranged whereby rotation of the shaft first engages the second and third switch arms to establish a first circuit and upon further rotation engaging the contacts on the first switch arm and bimetal element to establish a second circuit.

10. Switch mechanism comprising, in combination, support means including a plate member and a cylindrical member, said members being secured together, insulating means mounted on the cylindrical-member, a flexible switch member of beryllium copper alloy mounted by the insulating means having an L-shaped slot therein providing a first switch arm and a second switch arm, a third switch arm mounted by the insulating means, said third switch arm being substantially rigid and adapted to be engaged by the second switch arm, a flexible bimetal element mounted by the insulating means, said first switch arm and bimetal element being provided with cooperating contacts, individual terminal means associated with the switch member, the third switch arm and the bimetal element, a threaded bushing mounted on the support plate, a rotatable shaft having a threaded portion cooperating with the threaded portion of the bushing, a rigid strut of insulating material disposed between the rotatable shaft and the switchmember, the terminal associated with the switch member being adapted to be connected with one side of a current supply, the terminals associated with the third switch arm and the bimetal element being adapted to be respectively connected with a motor and an electrically energizable heater, said switch arms being arranged whereby rotation of the shaft in one direction first engages the second and third switch arms to establish a circuit through the motor and upon further rotation of the shaft to engage the contacts on the first switch arm and bimetal element to energize the circuit through said heater.

11. Switch mechanism comprising, in combination, support means, a switch member mounted by the support means shaped to provide a first switch arm and a second switch arm, said first and second switch arms being flexible, manually operable means mounted by the support means engagable with the switch member for actuating the first andsecond switch arms, a substantially rigid third switch arm mounted by the support means arranged to be engaged by the second switch arm to control a first circuit, a 'thermoresponsiveelement mounted by the support means, contacts carried by the first switch arm and said element arranged to be engaged and disengaged for controlling a second circuit, said first and second switch arms being movable by said manually operable means to positions whereby one circuit is established during periods that the other circuit is established.

No references cited.

L. A. WRIGHT, Assistant Examiner. 

1. SWITCH MECHANISM COMPRISING, IN COMBINATION, SUPPORT MEANS, A SWITCH MEMBER MOUNTED BY THE SUPPORT MEANS SHAPED TO PROVIDE A FIRST SWICH ARM AND A SECOND SWITCH ARM, SAID FIRST AND SECOND SWITCH ARMS BEING FLEXIBLE, MANUALLY OPERABLE MEANS MOUNTED BY THE SUPPORT MEANS ENGAGEABLE WITH THE SWITCH MEMBER FOR ACTUATING THE FIRST AND SECOND SWITCH MEANS, A SUBSTANTIALLY RIGID THIRD SWITCH ARM MOUNTED BY THE SUPPORT MEANS ARRANGED TO BE ENGAGED BY THE SECOND SWITCH ARM TO CONTROL A FIRST CIRCUIT, A THERMORESPONSIVE ELEMENT MOUNTED BY THE SUPPORT MEANS, CONTACTS CARRIED BY THE FIRST SWITCH ARM AND SAID ELEMENT ARRANGED TO BE ENGAGED AND DISENGAGED FOR CONTROLLING A SECOND CIRCUIT, SAID FIRST AND SECOND SWITCH ARMS BEING MOVABLE BY SAID MANUALLY OPEABLE MEANS TO POSITIONS WHEREBY THE FIRST CIRCUIT IS ESTABLISHED DURING THE PERIODS THAT THE SECOND CIRCUIT IS ESTABLISHED THROUGH THE FIRST SWITCH ARM AND THE THERMORESPONSIVE ELEMENT. 